Test 5: Variable Geometry Turbocharger Control - Suzuki GRAND VITARA 2005 Service Manual

Test 5: Variable geometry turbocharger control

Step
1 Engine stopped:
Check manually if the variable geometry control rod is
blocked.
Is the rod blocked?
2 At idle speed, with boost pressure control solenoid valve
control:
between of 70% and 85% opening cyclic ratio, disconnect
the electrical connector of the solenoid valve and check at
the same time if the rod controlling the variable geometry
blades moves.
Does the rod move from end stop to end stop?
3 Check the condition of the boost pressure control solenoid
valve connectors (corrosion, bent pins, etc.). Measure the
resistance of the solenoid valve referring to "Boost Pressure
Control Solenoid Valve Inspection: in Section 1C".
Is the solenoid valve in order?
4 Check the electric harness of boost pressure control
solenoid valve
Is there in good condition?
5 Reconnect the electrical connector of the boost pressure
control solenoid valve.
On the control diaphragm of the variable geometry blades,
disconnect the pipe coming from the solenoid valve.
Connect a pressure gauge in place of the diaphragm.
Engine at idling speed.
Is the vacuum pressure > 750 mbar?
6 Measure the vacuum pressure upstream of the boost
pressure control solenoid valve.
Is the vacuum pressure > 750 mbar?
Action
Engine General Information and Diagnosis:
Yes
Replace the
turbocharger.
The turbocharging
control circuit is
operating normally.
Go to Step 4.
Go to step 5.
Replace the
turbocharger.
Replace the boost
pressure control
solenoid valve.
1A-109
S5JB0B1104170
No
Go to Step 2.
Go to Step 3.
Replace the boost
pressure control
solenoid valve.
Repair as necessary.
Go to Step 6.
Check the vacuum
circuit and repeat the
test from the vacuum
pressure check.